Cloud Digital Leader Why Cloud Technology Can Transform Business Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  Firestore

  Why it's wrong here

  Firestore is a schemaless document database that stores data as nested documents and collections, not as tables with rows and columns. It lacks support for SQL, joins, foreign keys, and other relational integrity constraints, so a legacy relational schema cannot be directly migrated. The application would need to be rewritten to use Firestore's NoSQL query API and to model denormalized data, which is far from a minimal-effort migration.

• ✗

  Cloud Spanner

  Why it's wrong here

  Cloud Spanner is a fully managed, horizontally scalable relational database, but it uses a non-MySQL SQL dialect and does not support the MySQL wire protocol or MySQL-specific features like stored procedures and triggers. Existing application code using MySQL drivers and ORMs would need to be reworked to use Spanner's client libraries and GoogleSQL or PostgreSQL interface, which is a significant change. Additionally, Spanner's distributed transaction semantics and primary-key requirements may force schema alterations, making it inappropriate for a quick lift-and-shift.

• ✗

  Cloud Bigtable

  Why it's wrong here

  Cloud Bigtable is a wide-column NoSQL database optimized for high-throughput, low-latency time-series and key-value workloads; it does not support SQL, multi-table joins, or ACID transactions beyond single-row operations. A legacy relational database with normalized tables, foreign keys, and complex queries cannot be migrated as-is — the schema would have to be flattened and denormalized, and every data access path rebuilt. This would require substantial application redesign and is the opposite of a minimal-change migration path.

• ✓

  Cloud SQL for MySQL

  Why this is correct

  Cloud SQL for MySQL is a fully managed service that is tightly compatible with the MySQL wire protocol, SQL dialect, and client tools, so existing schemas, queries, stored procedures, and application code can be reused with almost no modification. It provides automatic failover to a synchronous standby replica, managed backups, and read replicas, meeting high-availability needs without changing the database engine. This makes it the natural choice for migrating a legacy on-premises MySQL database with minimal code changes and low operational overhead.

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